DE1150967B - Process for the preparation of dialkyl ethers of mixed polyalkylene glycols - Google Patents

Description

The invention relates to a process for the preparation of dialkyl ethers of mixed polyalkylene glycols; the process is characterized in that one mol of 4,4'-dihalodibutyl ether with more than 2MoI monoether from 1,2- or 1,3-glycols, 1,2- or 1,3-thioglycols or 1,2-diglycols and containing 1 to 4 carbon atoms Reacts alcohols in the presence of at least 2Mol alkali hydroxide at elevated temperature and the excess ίο of monoethers removed from the reaction mixture.

Suitable monoethers are, for. B. Ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, 3-methoxybutanol, Ethyl mercaptoethanol and diethylene glycol mono diethyl ether.

The reaction temperature is preferably from 120 to 160 ° C. The removal of the excess on monoethers is expediently carried out by distillation.

The dialkyl ethers of mixed polyalkylene glycols prepared according to the invention show very favorable temperature-viscosity behavior and generally have a very low pour point; they are also stable to shear. The dialkyl ethers can also be mixed with mineral oils and synthetic oils in any ratio, ζ. Β. those of the type _{containing the C 2} H ₄ O groups, as described, inter alia, in French patent specification 898 269. Mineral oils to which the dialkyl ethers of the present invention have been added show considerable improvements with regard to their temperature-viscosity behavior, with regard to their lubricating properties and with regard to shear stability and pour point. Synthetic oils to which the dialkyl ethers have been added also show considerable improvements with regard to temperature-viscosity behavior as well as with regard to lubricating properties and pour point. Since the dialkyl ethers produced according to the invention are very fluid, oils of higher viscosity can be converted into oils of lower viscosity with their help.

The previously known polyalkylene glycols and their ethers have the valuable properties

C ₂ H ₅ -O - (CHW ₈ - O -f (CHj) ₄ - O -

can be distilled without residue in a high vacuum under a pressure of 0.5 mm Hg at 162 to 165 ° C.

If, in the above-described reaction, production processes are used

of dialkyl ethers mixed

Polyalkylene glycols

Applicant:

Paint factories Bayer Aktiengesellschaft,
Leverkusen

Dr. Heinrich Morschel and Dr. Walther Lohmar,

Leverkusen,
have been named as inventors

of the dialkyl ethers prepared according to the invention not or not to the same extent.

example 1

In a mixture of 2388 g of 4,4'-dichlorodibutyl ether and 6000 g of ethylene glycol monoethyl ether carries one within 4 hours at temperatures between 120 to 130 ° C with stirring 1180 g 95% caustic soda and the mixture is heated for a further 12 hours while stirring 125 ° C. The unreacted amount of ethylene glycol monoethyl ether is then distilled at about 130 ° C and 10 mm Hg and treated the residue at 90 ° C with 3500 ml of water. After separating the aqueous layer, the remaining oily layer is neutralized with hydrochloric acid and washed with water. The oil is then heated in vacuo to remove water and low-boiling components, until an internal temperature of 190 ° C at 10 mm Hg is reached, and then filtered at 100 ° C. Of the diethyl ether of the formula thus obtained in a yield of 300 g

- (CH ₂ ) ^ - O - (CH ₂ ) ₂ - O - C ₂ H ₅

instead of the ethylene glycol monobutyl ether, one obtains the corresponding dibutyl ether of the formula

C ₄ H ₉ - O - (CH _{2) 2} -O - (CH ₂₎ - O - (CH _{2) 4} - O - (CH _{8) 2} - O - C ₄ H ₉

309 619/269

Claims (1)

3 4 Beismel 2 ^to dissolve the deposited salt with water added, the aqueous layer is then removed, and A mixture of 597 g of 4,4'-dichlorodibutyl ether, the remaining oily layer is with hydrochloric acid and 1200 g of diethylene glycol monomethyl ether is neutralized and washed with water. Then will Course of 5 hours at 135 to 140 ° C below 5 the unreacted amount of diethyl glycol mono- Added dropwise with 900 g of 5O ^fl / cent potassium methyl ether in vacuum at 178 ° C and 0.7 mm Hg offset. At the same time, the water is distilled off. distilled. After the mixture has been filtered at 100 ° C., it is then obtained If heated for 30 hours at 135 to 140 ° C, it becomes the dimethyl ether of the formula CH ₃ - O - (CH _{2) 2} -O - (CH _{2) 2} -O - (CH _{2) 4} -O - (CH ₂₎ - O - (CH _{2) 2} -O - (CH _{2) 2} —O — CH ₃ in a yield of 900 g. The separated salt is then stirred with 1000 ml of water dissolved at 80 to 90 ° C. After discovery isp3 is removal of the aqueous layer and after neutralization The remaining layer is separated from a mixture of 597 g of 4,4'-dichlorobutyl ether and the oily layer 1200 g of 3-methoxybutanol is water and the unreacted amount of 3-meth- the at 120 to 130 ° C with stirring with 326 g of oxybutanol by distilling in vacuo at 175 ° C scaly caustic soda added and then another 1.2 mm Hg. After filtering at 100 ° C Maintained at this temperature for 24 hours. The dimethyl ether of the formula is obtained CH ₃ - O - CH (CH ₃₎ - CH ₂ -CH ₂ -O - (CH _{2) 4} - O - (CH _{2) 4} - O - CH ₂ - CH ₂ - CH (CH ₃₎ - O - CH _3rd in a yield of 780 g. ■ - ■ heated, then at 90 ° C with 800 ml of water x, ■ ■ 1 α ² 5 sets and then neutralized with hydrochloric acid. After this .Example 4 Separation of the aqueous layer is taken from the To a mixture of 597 g of 4,4'-dichlorodibutyl remaining oily layer the remaining water and ether and 1000 g of ethyl mercaptoethanol are added to the unreacted amount of ethyl mercaptoethanol distilled off within 3 hours at 130 ° C with stirring in vacuo, finally at a temperature Add 326 g of flaky caustic soda. Here 30 door of 190 ° C and 0.3 mm Hg. After the filtration at the same time some water distills off. The mixture ren at 100 ° C is obtained from the diethyl ether is then set to 130 to 135 ° C for another 16 hours C ₂ H ₅ -S - (CH ₂ ) ₂ - O - (CH ₂ ) ₄ - O- (CH ₂ ) ₄ - O- (CH ₂ ) ₂ - S - C ₂ H ₅ in a yield of 727 g. ether with more than 2MoI monoether from 1,2- or 1,3-glycols, 1,2- or 1,3-thioglycols PATENT CLAIM: or 1,2-diglycols and 1 to 4 carbon atoms containing alcohols in the presence of Process for the production of dialkyl ethers 40 at least 2MoI alkali hydroxide with increased mixed polyalkylene glycols, thereby marked temperature converted and from the reaction draws that 1 mol of 4,4'-dihalodibutyl mixture removes the excess of monoethers. ® 309 619/269 6.63